Electrical receptacle.



C. D. PLATT.

'Ffq E Patented J 11110 26, 1917.

2 SHEETS-SHEET 2.

5 nventoi CYarezzaafl P/a/Z ED STATES CLARENCE D. PLATT, OF BBIDGEPOBT,CONNECTICUT.

ELECTRICAL RECEPTACLE.

Specification of Letters Patent.

Patented June 26, 1917.

To all whom it may concern: I

Be it known that I, CLARENCE D. PLATT, a citizen of the United States ofAmerica, residing at Bridgeport, Conn, have inventeda new and usefulElectrical Receptacle, of which the following is a specification.

The main object of my invention is to provide a receptacle in which itis impossible to accidentally short circuit the screw socket and thecenter contact, either with the hand or with a tool. Another object isto facilitate connection of wires to the terminals or binding posts sothat it will not be necessary to cut the wires for thepur-.

pose of attachment.

The first object is attained by a special" construction of a centercontact and the arrangement of connections leading thereto. The otherobject is attained by a special construction of the body of thereceptacle in relation to the terminals.-

Figure 1, is a side View of a receptacle embodying the improvements ofmy invention as shown in an outlet box, and with a cover plate shown insection.

Fig. 2, is a front View of a'receptacle embodying the improvements of myinvention.

Fig. 3, is a front view of the'insulating body of the receptacle, the'metal parts being removed Fig. 4, 1s a rear view of the receptacle. Fig.5, 1s a longitudinal sectional v1ew on an enlarged scale showing acenter con- I lug 19 which projects outwardly throug tact in theposition which it occupies when no plug orsocket in place and alsoshowing in dotted lines one of the intermediate positions taken by thecontact when insert-V ing a plug or lamp.

Fig. 6, is'a similar sectional view showing an attachment plug in placewith the circuit completed.

Fig. 7, is a perspective view of the center the rear.

The body is provided with an insulatin which the connecting screw 17passes and the grooves 20 and 21 at each side of the tip of the contactplate 35.

lug afl'ord passages for the conductor 22 so that the conductor may bereadily at tached by simply looping it over the lug and under the headof the binding screw 15. Continuous wires may thus be attached readilyto the terminals without the necessity of cutting them so as to provideends.

The screw socket 25 or shell, as it is sometimes called, is mounted in arecess 26 in thefront of the base and secured in place by screws such as27, 27 which pass through into nuts 28, 28 in the recesses in the rearof the base.

The yoke 29 carrying the spring arm 30 has openings 31 for the screws 27and thus is clamped against the bottom of the screw shell 25 by thesescrews. The center contact 32 is in the form of a hollow rivet or eyeletwhich is insulated from the arm 30 by an insulating bushing 33.

The contact plate 34 is secured to the base by the screw 18'and has oneend extended into the recess 26 beneath the end of the arm 30. Anothercontact plate 35 is secured to the base by the screw 17 and has one endter contact 32 and is substantially the same plane as the contact plate34. It will thus be seen that normally when there is no plug in thereceptaclev the screw shell'25 and the center contact 32 are both deadas neither is connected to a live part of the circuit.

When a plug or socket is screwed in as shown in Fig. 6, the centercontact is forced down so that the contact of the arm 30' contacts withplate 31 as shown dotted in Fig. 5 and then as the plug is forced to itsseat the lower face of the contact 32 engages the The circuit thenextends from the terminal plate 11 through the screw 17 the contactplate 35, the center contact 32 and through the plug. The other side ofthe circuit passes through terminal plate 12, screw 18, contact plate34, spring arm 30 and its base29 to the screw shell 25 and thencethrough the plug. As it requires considerable pressure to force thecenter contact 32 against the tip of the plate 35, it is practicallyimpossible to make con- 7 'nection with the finger and it is thereforeimpossible to get a. shock from either side of the line and it ispractically impossible to short circuit the contacts with thescrewdriver or other ordinary tool.

I claim l 1. An electrical receptacle comprising an offset from it andlocated beneath the cen- V insulating body having a recess, a screwshell .mounted therein, a spring contact connected 7 with the screwshell and carrying an ,insu-- ing body having a recess opening towardlated center contact, a center contact plate, circuit terminals, saidinsulated center contact and screw shell being normally dead, and meansfor automatically connecting the insulated center contact, the contactplate and screw shell in circuit when a plug is screwed into the screwshell.-

2. In an electrical receptacle, a screw shell, a spring arm electricallyconnected therewith, a center contact carried by said arm but insulatedtherefrom, and two stationary contact plates adapted to be engaged bysaid arm and by said center contact when said vcenter contact isdepressed in said-screw shell.

3. In an electrical receptacle, an insulating base, a screwshell carriedthereby, a center contact, an arm movable with but insulated from saidcenter contact and electrically connected with said screw shell, acontact plate adapted to be engaged by said arm,- and circuit terminalsconnectedto said 7 contact plates.

t. In an electrical receptacle, ascrew shell, an-arm having one endelectrically connected'with said screw shell, a stationary contact plateadapted to be engaged by the opposite end of said arm, a centrallylocated stationary contact plate and a. center contact carried by saidarm'but insulated theretip of the other contact racemes from and adaptedto engage said centrally located contact plate. I

'5. In an electrical receptacle, an insulatthe front and havingdiametrically opposite terminals adjacent the front, a contact plate atthe rear connected to one. of said terminals and having a tip portionextending into the bottom of said recess, a second'contact plate at therear having'one end extending into one side of said recess and connectedto the other terminal, a screw shell mounted in said recess, a contactmaking arm connected to said screw shell and adapted to engage one ofsaid'plates-at the side of said recess, a contact member carried by saidarm but insulated therefrom, adapted to engage the plate in the bottomof said recess.

6. In an electrical receptacle, an annular conducting member, a contactplate at one side of the base thereof, an arched spring arm connected atone-end of said annular member and having its other end adapted toengage said contact plate, a centrally located contact plate beneathsaid arm and a center contact carried by said arm but insulatedtherefrom and adapted to be forced into engagement with said centercontact plate after theend of said arm engages the other contact plate.

CLARENCE n. PLATT.

